Lax regulations are allowing more than 31,330 foreigners to work illegally in Vietnam, labor officials said at a conference this week.

Officials from the Ministry of Labor, War Invalids and Social Affairs suggested the government quickly establish an Employment Law to better manage foreign workers, Tien Phong (Vanguard) newspapersaid.

The illegal number of workers accounted for 40 percent of the 78,440 foreign workers in Vietnam as of September 2011, the labor ministry said.

Most of the illegal workers are manual laborers performing simple tasks.

Local labor authorities at the conference said the number increase in unskilled foreign workers in Vietnam will cause locals to be unemployed.

For example, a bauxite mining project in the Central Highlands province of Lam Dong, which includes the resort town of Da Lat, is using around 1,200 foreign workers.

Le Quang Trung, deputy director of the ministry's Job Department, said most foreign workers in Vietnam have come from other Asian countries such as South Korea, China and Japan.

Trung said many contractors who brought the workers to Vietnam did not comply with Vietnam's labor management laws.

Many local labor officials said the non-compliance should be blamed on the central government because the problem is rooted in the lack of regulations, from the Health Ministry and the Ministry of Industry and Trade in particular.